Method for manufacturing detecting sensor, detecting sensor, and transmission

ABSTRACT

A detecting sensor is disclosed having a magnet, a plurality of magnetic field detecting sensor elements, and a housing. The magnetic field detecting sensor elements have a plurality of adjacent, overlapped bodies and a plurality of terminals projecting from the bodies in a same direction. The housing is disposed over the magnet and plurality of sensor elements, and has first and second sensor holding members. The first sensor holding member is positioned on a first side of the housing and abutted against a surface of the body on a first side of the plurality of sensor elements. The second sensor holding member is positioned on a second side of the housing and abutted across a portion of a surface of the body of the sensor element on a second side of the plurality of sensor elements.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT International Application No.PCT/JP2012/005561, filed Sep. 3, 2012, which claims priority under 35U.S.C. §119 to Japanese Patent Application No. 2011-235986, filed Oct.27, 2011.

FIELD OF THE INVENTION

The present invention is generally related to detecting sensors, andmore specifically related magnetic field detecting sensors used inautomobiles.

BACKGROUND

It is well known that electronic control is becoming commonplace inautomobiles, and detecting sensors for detecting the operation ofvarious parts are quite often used. Generally these detecting sensorsmonitor whether or not the parts are at predetermined positions by usingmagnetism.

Specifically, multiplexed detecting sensors are responsible fordetecting the operation of an important part, such as a part involved incontrolling a running automobile. (see JP8-49575A and JP3-491587B). In amultiplexed detecting sensor, a plurality of sensor elements arepresent, allowing redundancy in the event a malfunction occurs in one ofthe sensor elements. When one sensor element malfunctions, detection canbe performed by using the other sensor element, or detection results ofone and the other of the sensor elements are compared to perform failurediagnosis of the sensor elements.

FIG. 14 shows an existing detecting sensor 1 manufactured by the presentapplicants. The detecting sensor 1 has a magnet 3 with a substantially Ushape member and two sensor elements 4A and 4B are held in an housing(not shown). A recess 3 a opens on one side of the magnet 3. In themagnet 3, a region A with no magnetic flux exists inside the recess 3 a.The two sensor elements 4A and 4B are positioned in the region A with nomagnetic flux.

When the detecting sensor 1 is mass-produced, it is important tomaintain high location accuracy for the magnet 3 and the sensor elements4A and 4B. This is because any variations in the positions of the sensorelements 4A and 4B with respect to the magnet 3, directly affect productaccuracy when using a plurality of detecting sensors 1.

To address this problem, the magnet 3 and the sensor elements 4A and 4Bare fixed to the housing (not shown) of the detecting sensor 1 with highaccuracy. However, the sensor elements 4A and 4B are positioned in thehousing (not shown) through body members 4 e, where an element body andfirst end of a terminal are embedded.

The disadvantage of this approach is that the body members 4 e aremolded from insulating resin, and thus do not have high moldingaccuracy. Therefore, there is a limit to improve the location accuracyof the magnet 3 and the sensor elements 4A and 4B by fixing the sensorelements 4A and 4B to the housing through the body members 4 e.

Location accuracy can be improved by increasing the molding accuracy ofthe bodies 4 e of the sensor elements 4A and 4B; however, such anapproach is prohibitively expensive. A need exists for an design thatuses an alternative manufacturing method that increases the locationaccuracy of the magnet 3 and sensor elements 4A and 4B at a low cost.

Further, a disadvantage of the conventional detecting sensor occurs whenthe object to be detected is a rotating body. When the conventionaldetecting sensor detects a rotating operation of the object, themagnetic field generated by the magnet is strained by the influence ofrotation of the object to be detected, and detection accuracy isaffected.

SUMMARY

It is therefore an object of the invention to provide a detecting sensorhaving a magnet, a plurality of magnetic field detecting sensorelements, and a housing. The magnetic field detecting sensor elementshave a plurality of adjacent, overlapped bodies and a plurality ofterminals projecting from the bodies in a same direction. The housing isdisposed over the magnet and plurality of sensor elements, and has firstand second sensor holding members. The first sensor holding member ispositioned on a first side of the housing and abutted against a surfaceof the body on a first side of the plurality of sensor elements. Thesecond sensor holding member is positioned on a second side of thehousing and abutted across a portion of a surface of the body of thesensor element on a second side of the plurality of sensor elements.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of example with reference tothe accompanying figures, of which:

FIG. 1 is a perspective view of an embodiment of an automobiletransmission;

FIG. 2 is a plan view of a portion in FIG. 1;

FIG. 3 is a view a detecting sensor with respect to the transmission;

FIG. 4 is a perspective view an embodiment of the detecting sensor;

FIG. 5 is a sectional view of the detecting sensor along a longitudinalaxis;

FIG. 6A is a plan view and FIG. 6B is a front view of a distal endportion of the detecting sensor;

FIG. 7A is a sectional view of the detecting sensor along A-A in FIG. 6,and FIG. 7B is a sectional view of the detecting sensor along B-B inFIG. 7A;

FIG. 8A is an enlarged perspective view of a distal end of the detectingsensor and FIG. 8B is an enlarged sectional view of the distal endportion of the detecting sensor;

FIG. 9 is a perspective view of a housing mold having terminal receivingholes;

FIG. 10 is a perspective view of a magnet positioned in the mold shownin FIG. 9;

FIG. 11 is a perspective view of the magnet and the sensor elementspositioned in the mold shown in FIG. 9;

FIG. 12 is a perspective view of a parking lock device in a parkingreleased state;

FIG. 13 is a perspective view of the parking lock device in FIG. 12 in aparking active state; and

FIG. 14 is a perspective view of the positions of sensor elements in amagnetic field generated by a magnet in a conventional detecting sensor.

DETAILED DESCRIPTION OF THE EMBODIMENT(S)

In the following, the present invention is described in detail based onan embodiment shown in the accompanying drawings.

FIGS. 1 to 11 are views for describing the configuration of a detectingsensor 10 in the present embodiment. In the following embodiments, thedetecting sensor 10 is used for detecting whether or not a partconstituting an automobile is at a particular position. In an exemplaryembodiment, the detecting sensor 10 is used for detecting whether amanual transmission of an automobile is positioned in a neutral state.

FIGS. 1 to 3 show an exemplary embodiment of the detecting sensor 10 ina transmission 200. The transmission 200 includes a plurality of gearssuch as first to fifth or first to sixth gears. When a driver of anautomobile operates a shift lever (not shown) in a longitudinaldirection along a traveling direction of the automobile and in atraverse direction perpendicular to the longitudinal direction, aparticular gear is selected. The rotation of an output shaft of anengine is transmitted to a drive shaft for driving a wheel via theselected gear. At this point, a rotation ratio (a speed reducing ratio,a speed increasing ratio) between the output shaft of the engine and thedrive shaft is determined by a gear ratio of the selected gear.

Although only the conceptual configuration of the transmission 200 isdescribed herein, one described in, for example, JP2002-235851A may bespecifically employed as the transmission 200.

In the transmission 200, three plate-like shift members 202A to 202C arepositioned to be stacked on each other to selectively connect a gear 201constituting each stage to the output shaft of the engine and the driveshaft. Each of the shift members 202A to 202C can slide in a directionperpendicular to the stacking direction (a direction perpendicular tothe paper face in FIG. 1). Gears 201 of different stages are selectedwhen the shift member slides in one direction along its surface from aneutral position, and when the shift member slides in another directionfrom the neutral position.

The shift members 202A to 202C as described above are operated by ashift arm 204 portion of a shift selecting shaft 203.

The shift selecting shaft 203 is positioned having a longitudinal axisparallel to the stacking direction of the shift members 202A to 202C.The shift selecting shaft 203 is positioned to reciprocate in an axialdirection along a through hole formed in a sleeve 205.

A selecting arm 206 for moving the shift selecting shaft 203 in theaxial direction is positioned at an upper end portion of the shiftselecting shaft 203. In the selecting arm 206, an intermediate portion206 b is rotatably supported on the sleeve 205, and a pin positioned atfirst end 206 a is coupled to the upper end portion of the shiftselecting shaft 203. A pin 206 c positioned at the second end of theselecting arm 206 is coupled to an operation wire or an operation rodconnected to the shift lever (not shown). In response to an operation inthe traverse (select) direction of the shift lever, the selecting arm206 rotates about the intermediate portion 206 b, causing the shiftselecting shaft 203 to reciprocate along the axial direction.

A shift rotor 207 is integrally positioned on an outer peripheral sideof the shift selecting shaft 203. A pin 207 a located on the outerperipheral side of the shift selecting shaft 203 is positioned on theshift rotor 207, and the pin 207 a is coupled to an operation wire or anoperation rod connected to the shift lever. (not shown) In response toan operation in the longitudinal (shift) direction of the shift lever,the shift rotor 207 rotates together with the shift selecting shaft 203about the longitudinal axis.

A projecting member 208 extends from the outer peripheral side of theshift arm 204.

When the shift lever is operated in the traverse direction, theselecting arm 206 is actuated to perform a select operation, causing theprojecting member 208 to move along the axial direction of the shiftselecting shaft 203, which is the stacking direction of the shiftmembers 202A to 202C. As the projecting member 208 moves along the axialdirection, the projecting member 208 can face any one of the shiftmembers 202A to 202C.

A projecting member receiving space 209, into which the projectingmember 208 can be inserted, is formed in each of distal end portions ofthe shift members 202A to 202C. When the projecting member 208 moves inthe stacking direction of the shift members 202A to 202C, the projectingmember 208 is fitted into the projecting member receiving space 209formed in any one of the shift members 202A to 202C.

When the shift lever is moved in the longitudinal direction and theprojecting member 208 positioned in the projecting member receivingspace 209 of any one of the shift members 202A to 202C, the shift rotor207 is actuated to perform a shift operation. As the shift selectingshaft 203 rotates about the longitudinal axis, the projecting member 208also rotates about the longitudinal axis. Since the projecting member208 is positioned in the projecting member receiving space 209 of one ofthe shift members 202A to 202C, that shift member 202A to 202C alsomoves to one side or another side from the neutral position.

As shown in detail in FIG. 3, a detection projection 210 extends awayfrom an outer peripheral portion of the shift arm 204. The detectionprojection 210 is positioned on a side of the shift arm 204 positionedopposite to the projecting member 208. In other embodiments, thedetection projection 210 is positioned on an outer peripheral portion ofthe shift selecting shaft 203.

The detecting sensor 10 is positioned close to and facing the detectionprojection 210. The detecting sensor 10 is fixed to a housing 211 of thetransmission 200 through a bracket 212. The detection projection 210 ispositioned closest to the detecting sensor 10 in a neutral state inwhich the shift lever and the shift members 202A to 202C are at theneutral position. The detecting sensor 10 detects whether or not thedetection projection 210 is at the close position, and thereby detectsthe rotation position of the shift arm 204.

As shown in FIGS. 4 and 5, the detecting sensor 10 is a redundant systemsensor including a housing 11, a magnet (a permanent magnet) 20 having asubstantially U shape in member that is held in the housing 11, a pairof sensor elements 30A and 30B, and a substrate 40.

The housing 11 includes, at first end, a connector receiving member 11 ato which a connector of a wire harness is connected, and, at the secondend, a sensor holding member 11 b that holds the magnet 20 and thesensor elements 30A and 30B.

The connector receiving member 11 a includes a tubular sleeve 12extending along a longitudinal axis, and a terminal holding member 13positioned within the sleeve 12, perpendicular to the longitudinal axisof the sleeve 12.

A plurality of L-shaped terminals 14 made of a conductive material areheld in the terminal holding member 13. In each of the terminals 14, afirst end 14 a is connected to a conductor constituting the wire harnessinside the sleeve 12, and the second end 14 b projects in a directionperpendicular to the longitudinal axis of the housing 11 from anintermediate portion of the housing 11.

A flat surface portion 11 c is formed on a side surface of the housing11. The substrate 40 has a rectangular shape extending along thelongitudinal axis of the housing 11, and is positioned along the flatsurface portion 11 c. A plurality of substrate holding arms 15 contactand secure the substrate 40, and are positioned along the flat surfaceportion 11 c. Each set of the substrate holding arms 15 is positioned soas to contact opposing sides of the substrate 40.

The second ends 14 b of the terminals 14 are inserted into through holes41 formed in the substrate 40, and electrically connected to a wiringpattern of the substrate 40.

As shown in FIGS. 6A,6B to 8A,8B, the sensor holding member 11 b of thehousing 11 holds the U-shaped magnet 20 such that both pole members 20 nand 20 s extend parallel along the longitudinal axis of the housing 11.Furthermore, the sensor holding member 11 b holds the magnet 20 suchthat distal end portions of the both pole members 20 n and 20 s areexposed on a distal end surface 11 d of the housing 11. Accordingly, themagnet 20 is buried in the housing 11 except for the distal end portionsof the both pole members 20 n and 20 s.

The sensor elements 30A and 30B are positioned facing each other in adirection along the longitudinal axis of the housing 11 in a recess 20a. The recess 20 a is positioned between the pole members 20 n and 20 sin the U-shaped magnet 20.

In an exemplary embodiment, the sensor elements 30A and 30B are hallelements, in each of which a hall element body 30C and first ends ofterminals 30 d are embedded in a body section 30 e made of an insulatingmaterial.

The sensor elements 30A and 30B are positioned with the body 30 eabutting against each other. The hall element bodies 30C of the sensorelements 30A and 30B are positioned adjacent to each other in the body30 e.

Positioning the hall element bodies 30C of the sensor elements 30A and30B adjacent to each other serves to minimize the influence of amagnetic (magnetic field) strain.

The second ends of the terminals 30 d are inserted into through holes 42formed in the substrate 40, and electrically connected to the wiringpattern of the substrate 40. The sensor elements 30A and 30B arepositioned such that the terminals 30 d project in the same directionfrom the body 30 e, perpendicular to the longitudinal axis of thehousing 11.

The sensor elements 30A and 30B as described above are held in thehousing 11 as described below.

The housing 11 includes a first sensor holding member 34 and a thirdsensor holding member 33 that hold the sensor elements 30A and 30Bfacing each other in the direction along an axis from the side of thesensor element 30A, and a second sensor holding member 36 and a fourthsensor holding member 35 that hold the sensor elements 30A and 30B fromthe side of the sensor element 30B.

The third and fourth sensor holding members 33 and 35 extend parallel toeach other along two sides of the bodies 30 e of the sensor elements 30Aand 30B, and abut against both sides of surfaces F1 and F2 of the bodies30 e.

The first sensor holding member 34 has a columnar shape positionedsubstantially in a center portion of the body 30 e of the sensor element30A, and extending toward the body 30 e from a perpendicular direction.A distal end portion 34 b of the sensor holding member 34 abuts againstthe center portion of the surface F1 of the body 30 e.

The second sensor holding member 36 extends along the body 30 e in adirection perpendicular to the sensor holding members 35 located on theboth sides of the body 30 e of the sensor element 30B. The sensorholding member 36 abuts against the surface F2 of the body 30 e of thesensor element 30B to form a substantially H shape together with theholding members 35 and 35 on the both sides.

To manufacture the detecting sensor 10, a magnet holding member 110 forholding the magnet 20 and a sensor element holding member 120 forholding the sensor elements 30A and 30B are positioned in a mold 100 forforming the housing 11 by resin molding as shown in FIG. 9, and thehousing 11 is formed using the mold 100.

As shown in FIGS. 9 and 10, the magnet holding member 110 holds themagnet 20 by a plurality of holding projections 111.

As shown in FIGS. 9 and 11, the sensor element holding member 120includes terminal receiving holes 121 into which the terminals 30 d ofthe sensor elements 30A and 30B are respectively inserted. By insertingthe terminals 30 d into the terminal receiving holes 121, the sensorelements 30A and 30B are respectively held by the mold 100.

In a state in which the openable mold 100 is opened, the magnet 20 andthe sensor elements 30A and 30B are held in the mold 100 by the magnetholding member 110 and the sensor element holding member 120. The mold100 is closed in this state, and resin is injected into the mold 100.

At this point, particularly for the sensor holding member 34 extendingin a columnar shape, the resin in a molten state flows from the side ofa proximal end portion 34 a to the side of the distal end portion 34 b.Accordingly, the sensor elements 30A and 30B are biased against theholding members 35 and 36 on the opposite side.

The mold 100 is opened after curing of the resin, and the detectingsensor 10 is removed. The detecting sensor 10 is thereby obtained.

A bottomed tubular cover (not shown) is mounted to the detecting sensor10 so as to cover the magnet 20, the sensor elements 30A and 30B, andthe substrate 40.

In accordance with the aforementioned embodiments, in the detectingsensor 10, the sensor elements 30A and 30B are formed integrally withthe housing 11, with the housing 11 being disposed over the magnet 20and the sensor elements 40A and 30B. The sensor elements 30A and 30B arepositioned and fixed by inserting the terminals 30 d into the mold 100used in molding, so that the sensor elements 30A and 30B can bepositioned with respect to the housing 11 with high accuracy. Therefore,high detection accuracy can be maintained for the sensor elements 30Aand 30B.

Moreover, this is achieved only by forming the terminal receiving holes121 in the mold 100, so that high detection accuracy can be consistentlybe achieved at low cost.

Further, in the detecting sensor 10, the sensor elements 30A and 30B areheld by the sensor holding members 33, 34, 35, and 36 in abutmentagainst the surfaces F1 and F2 of the body 30 e and 30 e. Since thesensor elements 30A and 30B are sandwiched in a state facing each otherby the sensor holding members 33, 34, 35, and 36, the sensor elements30A and 30B held in a repeatable, consistent manner. Even further, sincethe sensor holding members 33, 34, 35, and 36 abut against only aportion, not the entire surface, of the surfaces F1 and F2 of the body30 e, heat dissipation properties of the sensor elements 30A and 30B canbe ensured.

The detecting sensor 10 as described in the embodiments above, candetect whether or not the detection projection 210 formed on therotating sleeve 205 is at a prescribed position (a neutral position) ina non-contact manner. The non-contact detecting sensor 10 exhibitsexcellent reliability since the detecting sensor 10 has no movableportion and thus has a fewer failures as compared to a contact switch.

Furthermore, in the detecting sensor 10, the body 30 e and 30 e of thesensor elements 30A and 30B abut against each other, so that thedetecting sensor 10 can be reduced in size, easily positioned in thetransmission 200, and mounted at low cost.

Also, while an object to be detected is the shift arm 204 rotatingtogether with the shift selecting shaft 203, the influence of a magnetic(magnetic field) strain can be minimized since the hall element bodies30C and 30C of the sensor elements 30A and 30B are positioned adjacentto each other in a plurality of adjacent, overlapping bodies 30 e and 30e. The detection accuracy of the detecting sensor 10 can be therebyimproved.

Although the detecting sensor 10 has been described in the aboveembodiments for detecting whether or not the shifting of the manualtransmission of the automobile is in the neutral state, those ofordinary skill in the art would understand that the detecting sensor 10may be used in other applications. For example, the detecting sensor 10may be used for detecting whether or not an automatic transmission is ina parking state, as described below based on FIGS. 12 and 13.

First, a parking lock device 300 of an exemplary automatic transmissionis described by reference to FIG. 12. The parking lock device 300 isapplied to a transmission that can establish a predetermined gear speedby operating a meshing clutch positioned on a gear shift shaft by ashift rod 310 connected to and actuated by an actuator M. FIG. 12 showsthe parking lock device 300 in a neutral state.

The parking lock device 300 includes a parking gear 350 that ispositioned on a reverse idle shaft moving in conjunction with the driveshaft when the vehicle is stopped, a parking pawl 340 that can beengaged with the parking gear 350, and a parking rod 330 that moves inconjunction with the shift rod 310 to actuate the parking pawl 340. Theparking lock device 300 can bring the parking gear 350 into a lock stateby transmitting the operation of a shift member 320 formed integrallywith the shift rod 310 to the parking pawl 340 via the parking rod 330.

In the parking lock device 300, the shift rod 310 can axially rotate andselectively stop at three positions: a neutral position, a reverseposition, and a parking position, in a clicked manner. The shift rod 310is detected to be in a parking state or not when the shift member 320integrated therewith axially moves by the actuator M, and the detectingsensor 10 detects the position.

To this end, three detent grooves 310 a, 310 b, and 310 c are formed inthe shift rod 310, so that the shift rod 310 is at the neutral positionwhen a detent ball 367, urged by an spring (not shown), engages with thedetent groove 310 b, and at the parking position when the detent ball367 engages with the detent groove 310 c. Therefore, when the shift rod310 is axially rotated from the neutral state to the parking state, theshift rod 310 moves upwardly in the drawing.

A shift fork 311 and a coupling beam 312 are formed integrally with theshift rod 310. The coupling beam 312 integrally couples the shift rod310 to the shift member 320. A locking claw 313 is also formedintegrally with the coupling beam 312.

The shift member 320 includes a cam member 321 and a detection arm 325.

A cam groove 322 that penetrates through the cam member 321 and opens atfirst end is formed in the cam member 321, and first end side of a camplate 323 is inserted into the cam groove 322 through the opening. Inthe cam plate 323 where first end side is set to a large width, theactuator M is connected to the second end side, and when the actuator Mforwardly and reversely rotates the cam plate 323, the shift rod 310moves up and down. For example, when the actuator M is forwardly rotatedcounterclockwise, the cam plate 323 presses the cam member 321 upwardlyin the drawing, and the shift rod 310 moves up. In the following, up,down, left, and right indicate directions in the drawings.

The detection arm 325 is formed integrally with an upper portion of thecam member 321, and raised and lowered in association with theup-and-down movement of the cam member 321. A detection projection 326is formed at a distal end of the detection arm 325, and the detectingsensor 10 is positioned facing and in close proximity to the detectionprojection 326. A relative positional relationship between the detectingsensor 10 and the detection projection 326 is changed between theneutral state and the parking state, so that the detecting sensor 10 candetect whether or not the state is in the parking state, by thedetecting sensor's 10 proximity to the detection projection 326.

The parking rod 330 transmits the up-and-down movement of the shiftmember 320 (the shift rod 310) to the parking pawl 340. The parking rod330 is coupled to the locking claw 313 of the coupling beam 312 througha swing arm 335. The swing arm 335 includes a locking claw 336 that isengaged with the locking claw 313 on first end. The swing arm 335 alsoincludes a rod receiving hole 337 on a second end, where a distal endbent in an L shape of the parking rod 330 is held by passing through therod receiving hole 337. The swing arm 335 further includes a lockingprojection 338 positioned below the rod receiving hole 337 and engagedwith a locking spring member 357. A positioning rod 339 is positioned onone side surface of the swing arm 335, and the swing arm 335 performsswinging motion about the axis of the positioning rod 339. Therefore,when the shift member 320 is moved up by the actuator M, the swing arm335 rotates clockwise in conjunction with the shift member's 320 motion,and the parking rod 330 moves down along an axis substantially parallelto the longitudinal axis of the shift rod 310. Conversely, when theshift member 320 moves down, the swing arm 335 swings counterclockwise,and the parking rod 330 moves up.

An arc-shaped groove 339 a continuous in a circumferential direction isformed in the outer periphery of the positioning rod 339, and a columnarsupport pin 334 is positioned into the groove 339 a. The support pin 334regulates movement of the swing arm 335 in an axial direction of thepositioning rod 339 while allowing the rotational movement of the swingarm 335.

A cam member 352 is slidably fitted to the parking rod 330. The cammember 352 includes an equal-diameter member 352 a and a tapered member352 b whose diameter is gradually decreased from a lower end of theequal-diameter member 352 a. The cam member 352 applies a downward forcethrough a compressed coil spring 353 positioned around the parking rod330. When the parking rod 330 moves down in the parking state, the cammember 352 applies a great downward force than the parking rod 330.

A cam receiving member 340 b of the parking pawl 340 and a cam receivingmember 354 a of a parking rod holder 354 are positioned near the cammember 352. The cam receiving member 340 b and the cam receiving member354 a include tapered surfaces corresponding to the tapered member 352 bon their surfaces. Since the parking rod 330 is positioned relativelyhigh when in the neutral state shown in FIG. 12, the cam member 352 ispressed against the cam receiving member 340 b and the cam receivingmember 354 a by a relatively weak force. The position of the parking rodholder 354 is fixed.

The parking pawl 340 locks and unlocks the parking gear 350 inconjunction with the operation of the parking rod 330.

The L-shaped parking pawl 340 is swingably supported in a bend portionby a support shaft 362 whose position is fixed. The parking pawl 340includes an engagement claw 340 a, formed on a first end of the parkingpawl 340, engageable with a engagement claw receiving groove 350 aformed in the outer periphery of the parking gear 350, and the camreceiving member 340 b formed on a second end of the parking pawl 340.

The engagement claw 340 a moves away from the parking gear 350 through aforce applied to the parking pawl 350 by a torsional spring 355positioned on the outer periphery of the support shaft 362. In theneutral state, when the engagement claw 340 a is positioned away fromthe engagement claw receiving groove 350 a, a distance between the camreceiving member 340 b and the cam receiving member 354 a of the parkingrod holder 354 is reduced. In the parking state, the parking rod 330moves down, causing the cam member 352 to also be pressed down, suchthat the cam member 352 is pushed into a space between the cam receivingmember 340 b and the cam receiving member 354 a. Since the position ofthe cam receiving member 354 a is fixed, the parking pawl 340 rotatescounterclockwise when a force that the cam receiving member 340 breceives from the tapered member 352 b becomes larger than a force thatthe parking pawl 340 receives from the torsional spring 355.

The parking gear 350 is fixed to the reverse idle shaft (not shown)moving in conjunction with the drive shaft when the vehicle is stopped,and the parking state is ensured by locking the parking gear 350.

The parking gear 350 is positioned corresponding to the engagement claw340 a of the parking pawl 340, and when the parking pawl 340 rotatescounterclockwise as described above, the engagement claw 340 a isinserted into the engagement claw receiving groove 350 a to lock theparking gear 350.

Next, the operation of a process in which the parking lock device 300 isshifted from the neutral state to the parking state is described byreference to FIG. 13.

When the shifting is changed from the neutral state to the parkingstate, the actuator M rotates the cam plate 323 counterclockwise.Accordingly, the shift member 320 moves up, and the parking pawl 340follows the operation of the swing arm 335 and the parking rod 330 torotate counterclockwise from a position in FIG. 12 to a position in FIG.13. As a result, the parking gear 350 is locked.

In this state, the cam member 352 is positioned between the camreceiving member 340 b and the cam receiving member 354 a. When theparking rod 330 moves down to the parking state, the locking projection338 is displaced downward across a distal end of the locking springmember 357, so that the parking rod 330 is prevented from moving up bymistake. Therefore, the parking lock state is stably maintained.

When the shift member 320 moves up, the detection projection 326 alsofollows the movement, and is displaced upward across the distal end ofthe locking spring member 357. The proximity of the detection projection326 to the detecting sensor 10 differs between the neutral state and theparking state. Therefore, when the detection projection 326 is in closeproximity to the detecting sensor 10, the detecting sensor 10 detectsthe displacement of the detection projection 326 to determine whether ornot the state is in the parking state.

The mounting position of the detecting sensor 10 is not limited to theaforementioned position, and may be installed close to another memberwhose position moves in conjunction with the shift rod 310. For example,the detecting sensor 10 may be installed in close proximity to an upperend of the shift rod 310, or close to an upper end of the parking rod330.

Although the present invention has been described using embodimentswhere the detecting sensor 10 is used in an automobile for detecting theposition of a part as an example, the present invention is not limitedto the application.

Although the magnet 20 has been described in the above embodiments ashaving a substantially U shape member, the magnet 20 is not limited tothe U-shape, but may also have another appropriate shape.

Further, as long as the same effects as those described in the aboveembodiments are obtained, the arrangement, the installed number, and/orthe shape of the sensor holding members 33, 34, 35, and 36 may have aconfiguration other than those described above.

sensor elements that detect a change in the magnetic field generated bythe magnet;

In addition to the advantages described above, further advantagesinclude enhanced heat dissipation properties of the sensor elements30A,30B, since the sensor holding members 34,36 contact only a portionof the body 30 e of the sensor elements 30A,30B

Another advantage is that the detecting sensor 10 is reduced in size,easily positioned, and mounted at low cost without requiringmodifications to the object being detected. Such advantages are realizedbecause the bodies 30 e are positioned overlapping, with the surfaces ofthe bodies 30 e abutting against the adjacent bodies 30 e.

Another advantage is that by arranging the sensor elements 30A,30Badjacent to each other, the influence of the magnetic (magnetic field)strain can be minimized, and the detection accuracy can be improved.Also, by decreasing a gap between the sensor elements 30A,30B, thedetecting sensor 10 can be reduced in size, positioned with a higherdegree of freedom, and easily mounted.

Yet another advantage is that the above embodiments of the detectingsensor 10 stably exhibits high detection accuracy at low cost.

Another advantage is that during the manufacturing process, each of thesensor elements 30A,30B are fixed to the mold 100 by inserting theterminals of the sensor elements 30A,30B into the terminal receivingholes in the mold 100, so that the sensor elements 30A,30B can bepositioned with respect to the mold 100 with high accuracy. By injectingthe molten resin into the mold 100 in this state to form the housing 11,the detecting sensor 10 can be formed while the sensor elements 30A,30Bare positioned with respect to the magnet 20 with high accuracy. Such anadvantage is achieved by forming the terminal receiving holes 121 in themold 100, so that the above effects can be obtained at low cost.

The embodiments described above may be also freely selected or changedinto other constitutions without departing from the scope of the presentinvention.

What is claimed is:
 1. A detecting sensor comprising: a magnet; aplurality of magnetic field detecting sensor elements having a pluralityof adjacent, overlapped bodies and a plurality of terminals projectingfrom the bodies in a same direction; a housing disposed over the magnetand the plurality of sensor elements, and having a first sensor holdingmember positioned on a first side of the housing and abutted againstonly a portion of a surface of the body on a first side of the pluralityof sensor elements; and a second sensor holding member positioned on asecond side of the housing and abutted across only a portion of asurface of the body of the sensor element on a second side of theplurality of sensor elements.